Fullerphone details needed

[David Dunlop]

Great photos, everyone! Thanks. I should not have a problem scaling an appropriate font from them.

A quick question you have raised, however, is what are 'YA' numbers and how do these relate (if at all) to 'ZA' numbers?

Hmmm. I guess, technically, that is two questions.

David

[Bruce MacMillan]

YA are to do with telephony and ZA are to do with wireless.

These are VAOS numbers, Vocabulary of Army Stores.

There are sources on the net that list what the various numbers are.

[David Dunlop]

I had a closer look at the side of the box where original markings should be and lo and behold, they are still visible under the postwar paint. Three lines as per the photo Bruce M posted. No sign of the "YA Line" at the very top. Also noticed Northern Electric also made the headphone assemblies (two metal head band style) and the Buzzer Mk. F pieces as well.

Both units were made in 1943, about 100 numbers apart in Serial Numbers, but the schematic plates inside the back of the boxes are different. Looks like more than one manufacturer may have been involved in the manufacture of the wooden cases.


David

[David Dunlop]

Just noticed the tool mounted on the strap of your Fullerphone. What is it? I have seen a lot of those straps, nearly always fastened to Signals equipment like RCU's, Fullerphones etc and wondered what the three small canvas loops and the small adjustable canvas strap secured. I think the strap has a YA number on it (YA 1532 or 1632) sometimes stamped in black. Don't think I have run across a maker code or date on any and some are completely blank. Both my Fullerphones have these straps. One has the YA stamp only and the other is blank. The small buckled straps on both have a reddish dipped end to keep it from fraying. May need to find a few more if them.

David

[universalgrl]

http://www.wftw.nl/ful.html

Every thing you need to know about the fuller phone.
The tool is actually the ground spike for the L 2 terminal on the phone as the fuller operates on a 1 wire system.

[David Dunlop]

Thanks, Roberta.

The detail bits for wireless equipment never ceases to amaze me. In these parts, I have never seen a fullerphone sold with a ground spike, so I guess somewhere there must be boxes of them waiting to be discovered.

David

[cletrac (RIP)]

Here's one on ebay
Fullerphone

[Chris Suslowicz]

Originally Posted by David Dunlop

Thanks, Roberta.

The detail bits for wireless equipment never ceases to amaze me. In these parts, I have never seen a fullerphone sold with a ground spike, so I guess somewhere there must be boxes of them waiting to be discovered.

David

They've probably been mostly melted down for scrap by now, but the basic design was still in service up to the 1990s and may still be around. (It did, however get dramatically cheapened over time.) Top to bottom: Modern (cheap & nasty) bent mild steel rod with sprayed zinc coating that comes off easily. Next two are 1942 Canadian manufacture to the original specification: machined square bar with the crosspiece made from some of the turned bar welded on and then ground flush with the sides, terminal is (I think) 2BA, properly countersunk and with a wire loop retainer for the knurled nut. Bottom one is WW2 British mass production, bent square bar but still with the properly fitted terminal.The mottled effect on the Canadian pins is the remnant of hardened preservative, the British pins are just oxidised, probably mostly from the blacksmithing process.

Chris.

[Chris Suslowicz]

Originally Posted by David Dunlop

Thanks, Roberta.

The detail bits for wireless equipment never ceases to amaze me. In these parts, I have never seen a fullerphone sold with a ground spike, so I guess somewhere there must be boxes of them waiting to be discovered.

David

One reason for that is because the fullerphone wasn't used in the same way as during WW1; it was mainly intended for static warfare in the "danger zone" where earth return circuits could be easily intercepted using a couple of earth pins and an amplifier. For WW2 things were a lot more fluid and the forward positions mainly used Telephone Set 'D' with twin cable if possible (in India they were restricted to earth return circuits a lot due to cable shortages and the speed of the advance). One major use of the fullerphone was on "phantom" circuits between headquarters and signal centres for passing routine (and coded) traffic. (Using a "Superposing transformer" you can piggyback a DC telegraphy (fullerphone or teleprinter) on top of a speech circuit without mutual interference. The ideal setup is two 2-wire circuits, followed by 2 wires and an earth return, with the last resort being the fullerphone in series with the telephone on a single wire and earth.

The 10-line UC switchboard had an optional "superposing unit 3 transformer" that allowed 3 fullerphone or teleprinter circuits to be piggybacked on any of the 10 lines (1 per line, naturally!).

Chris.